JPH11248150A - Combustor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a combustor which is able to accurately combust a burner with a demanded quantity of heat for combustion. SOLUTION: A gas supply line 2 for introducing gas is connected to a burner 1 which is of the type that switches burning faces according to a quantity of heat for combustion. The gas supply line 2 is provided with a proportional valve 6 for controlling the amount of gas supplied to the burner 1. A bypass line 26 having a straightening effect for gas is arranged at an upstream of the gas supply line 2 from the proportional valve 6. Further, the bypass line 26 is provided with a gas flow amount sensor 18 for detecting the amount of gas supplied to the burner 1. With data showing the relationship between the gas flow amount and the combustion quantity of heat being given in advance, the gas flow amount corresponding to a demanded combustion quantity of heat is detected on the basis of the related data, followed by controlling the proportional valve 6 so that the gas flow amount detected by the gas flow amount sensor 18 matches the obtained gas flow amount. Thus, an amount of gas corresponding to a demanded combustion quantity of heat can be surely supplied to the burner 1, thereby performing accurate control of the combustion quantity of heat.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a combustion apparatus such as a water heater provided with a burner for burning fuel gas.

[0002]

2. Description of the Related Art FIG. 4 is a model diagram showing an example of a water heater as a combustion device. The water heater is provided with a burner 1 as shown in FIG. This burner 1 is provided with a plurality of combustion surfaces (in the example shown in FIG.
Surface, B surface, and C surface).

A gas supply passage 2 for introducing fuel gas to the burner 1 is provided. The gas supply passage 2 branches off via a gas nozzle (not shown) provided in a nozzle holder (not shown). Opening / closing valves 3a, 3b, and 3c for supplying and shutting off fuel gas to the respective combustion surfaces are interposed in the branched passages, respectively. An on-off valve 5 for opening and closing the gas supply passage 2 upstream of the branch portion and a gas supply amount control means for controlling the supply amount of fuel gas supplied to the burner 1 by a valve opening degree. A certain proportional valve 6 is provided.

For example, the fuel gas is supplied from the gas supply passage 2 to the burner 1 with the on-off valve 3a opened and the on-off valves 3b and 3c closed, and the burner is burned. Is burned in a one-sided combustion state (first stage combustion state), and by opening the on-off valve 3b from this state, the burner 1 is in a two-sided combustion state in which the A surface and the B surface burn (the second stage combustion state). ), It is possible to burn with a larger amount of combustion heat than at the time of the above-described one-side combustion, and by opening the on-off valve 3c, the burner 1 becomes A
A three-sided combustion state in which all of the surfaces B, C, and C burn (3
(Combustion state of the second stage), and it becomes possible to burn with a larger amount of combustion heat than in the above two-sided combustion. As described above, the burner 1 shown in FIG. 4 is a burner of a multi-stage capacity switching type capable of switching each combustion surface.

[0005] A combustion fan 8 is provided, and air (supply) is supplied to the burner 1 by driving the combustion fan 8.
And exhaust gas generated by combustion of the burner 1 is discharged to the outside through an exhaust passage (not shown).

A heat exchanger 10 is provided above the burner 1, and a water supply passage 11 for guiding water from a water supply source to the heat exchanger 10 is connected to an inlet of the heat exchanger 10.
One end of a hot water supply passage 12 is connected to the outlet side of the heat exchanger 10, and the other end of the hot water supply passage 12 is led to a shower in a kitchen or a washroom.

The water supply passage 11 is provided with an incoming water temperature sensor 13 for detecting the temperature of incoming water flowing through the passage 11 and a water amount sensor 14 for detecting the flow rate of water flowing through the passage 11. The hot water supply passage 12 is provided with a hot water temperature sensor 15 for detecting the temperature of hot water to be supplied.

Further, a controller 16 is provided in the water heater, and a remote controller 17 is connected to the controller 16 by signal. The remote controller 17 is provided in the vicinity of a hot water supply place such as a kitchen or a lavatory, and the remote control 17 is provided with a hot water degree setting means for setting a hot water temperature.

The control device 16 controls the hot water supply operation of the water heater. For example, a hot water tap (not shown) provided in a kitchen or the like is opened and the water flow detected by the water amount sensor 14 is detected. When the flow rate becomes equal to or higher than a predetermined hot water supply operation flow rate, the combustion fan 8 is started to rotate to supply air to the burner 1 and start burning the burner 1, and the hot water supply set by the remote controller 17 is set. The combustion heat amount of the burner 1 is controlled so that hot water at a set temperature can be supplied, the hot water of the heat exchanger 10 is heated by the combustion heat of the burner 1 to generate hot water, and the hot water is passed through a hot water supply passage 12 to a desired temperature. Supply hot water to the hot water supply location. When the hot water tap is closed and the water amount sensor 14 detects the stoppage of water supply, the on-off valve 5
To stop the combustion of the burner 1, stop the rotation of the combustion fan 8, and prepare for the next hot water supply operation.

The combustion heat quantity control of the burner 1 is performed, for example, by
The remote controller 1 determines the incoming water of the flow rate Q detected by the water amount sensor 14 from the incoming water temperature Tin detected by the incoming water temperature sensor 13.
7, the amount of feedforward heat necessary to increase the hot water supply set temperature Tst to a heat amount taking into account a feedback heat amount for correcting a deviation amount of the tap water temperature Tout detected by the tap water temperature sensor 15 with respect to the hot water supply set temperature Tst. Is controlled by controlling the valve opening of the proportional valve 6 so that the burner 1 can perform combustion with the amount of combustion heat that can be supplied to the water passing through the heat exchanger 10 (that is, in order to control the valve opening). Is controlled by controlling the amount of fuel gas supplied to the burner 1 (by controlling the proportional valve drive current Is).

For example, combustion heat quantity control characteristic data as shown in FIG. 5A, which is relation data between the combustion heat quantity and the proportional valve drive current Is, is given in advance. As described above, the burner 1 shown in FIG. 4 is a burner of a multi-stage capacity switching type. Therefore, the combustion heat quantity control characteristic data is given for each combustion stage, and the burner 1 shown in FIG. The heat quantity control characteristic data L1 is data relating to the first combustion stage, the combustion heat quantity control characteristic data L2 is data relating to the second combustion stage, and the combustion heat control characteristic data L3 is data relating to the third combustion stage. It is. When the required amount of combustion heat is, for example, the amount of heat Pex shown in FIG. 5A, the combustion heat amount control characteristic data L2 is selected, and the target proportional valve drive current Iex is detected based on the selected data. The proportional valve drive current Is of the proportional valve 6 is controlled so that the target proportional valve drive current Iex is obtained in the two-sided combustion state (the second stage combustion state) in which the on-off valves 3a and 3b are opened. The amount of fuel gas from which the heat amount Pex can be obtained is supplied to the burner 1. In this way, the combustion calorie control is performed.

Further, when the combustion heat quantity control is performed as described above, the rotation of the combustion fan 8 is performed so that air corresponding to the amount of fuel gas supplied to the burner 1 can be supplied to perform good burner combustion. Control is performed. In order to control the rotation of the combustion fan 8, airflow control characteristic data as shown in FIG. 5B, which is relational data between the proportional valve drive current Is and the fan airflow, is given for each combustion stage. . The air volume control characteristic data F1 is data relating to the first combustion stage, the air volume control characteristic data F2 is data relating to the second combustion stage, and the air volume control characteristic data F3 is 3
This is data on the second combustion stage. After the target proportional valve drive current Is corresponding to the required amount of combustion heat is detected as described above, the fan air amount corresponding to the detected proportional valve drive current Is is determined according to the combustion stage by the above-described combustion heat amount control. Detection is performed based on the airflow control characteristic data, and the rotational drive of the combustion fan 8 is controlled so as to achieve the detected fan airflow.

As described above, by performing the combustion heat amount control and the fan air amount control, good burner combustion is performed, and hot water at a hot water set temperature desired by a user of the hot water can be supplied.

[0014]

However, if the combustion heat amount is controlled based on the relational data between the combustion heat amount and the proportional valve drive current as described above, the required combustion heat amount may not be obtained, and the hot water supply set temperature may not be obtained. Hot water may not be supplied stably. This is because the relationship between the amount of combustion heat and the proportional valve drive current may deviate from the previously provided relationship data. In other words, the relationship between the proportional valve drive current and the amount of fuel gas supplied to the burner 1 (that is, the flow rate of fuel gas supplied to the burner 1) is caused by the pressure fluctuation of the fuel gas supplied from the fuel gas supply source and the like. This is because they may shift.

For this reason, for example, the proportional valve drive current Iex shown in FIG. 5A is supplied to the proportional valve 6 to control the valve opening and burn the burner 1 with the combustion heat Pex. Nevertheless, the flow rate of the fuel gas supplied to the burner 1 fluctuates and the burner 1
A situation arises in which combustion of the gas is performed. Further, since the rotation of the combustion fan 8 is controlled so that the air flow corresponding to the proportional valve drive current Iex is supplied, if the amount of fuel gas supplied to the burner 1 is shifted as described above, The amount of air corresponding to the amount of fuel gas supplied to the burner 1 cannot be supplied, and a shortage of air or an excessive amount of air deteriorates the combustion state, thereby deteriorating the combustion efficiency.

Further, as shown in FIG.
Is a multi-stage capacity switching type burner, the combustion heat amount control characteristic data must be given for each combustion stage, and the gas flowing through the gas supply passage 2 downstream of the proportional valve 6 is required. Since the pressure loss of each combustion stage is different for each combustion stage, these combustion heat quantity control characteristic data must be created in consideration of the difference in the pressure loss, which is very troublesome, and the pressure loss is liable to fluctuate. For this reason, there is a problem that the relationship between the proportional valve drive current and the amount of combustion heat tends to deviate from the above relational data, and the above-mentioned problem of excess or deficiency of the amount of combustion heat and deterioration of the combustion state increase.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problem, and an object of the present invention is to make it easy to control the amount of combustion heat, and furthermore, to ensure the burner with good combustion and the required amount of combustion heat. An object of the present invention is to provide a combustion device capable of burning.

[0018]

Means for Solving the Problems To achieve the above object, the present invention has the following structure to solve the above problems. That is, a first aspect of the present invention provides a burner; a gas supply passage for introducing fuel gas to the burner; and a gas supply amount control provided in the gas supply passage and controlling a fuel gas supply amount to the burner with a valve opening. Means; a bypass passage provided in the gas supply passage; gas flow detection means provided in the bypass passage for detecting a flow rate of fuel gas supplied to the burner; and a flow rate of fuel gas supplied to the burner. A required gas flow rate detecting section for providing a relational data with the calorific value of the burner in advance and obtaining a fuel gas flow rate corresponding to the required calorific value of the burner based on the relational data; a fuel detected by the gas flow rate detecting means; The gas opening amount of the gas supply amount control means is controlled so that the gas flow rate becomes the fuel gas flow rate obtained by the required gas flow rate detection section, and the combustion heat quantity of the burner is controlled. A flow control unit; with a configuration that is provided is a means to solve the problem.

According to a second aspect of the present invention, there is provided means for solving the above-mentioned problem by a configuration in which the bypass passage constituting the first aspect of the invention is provided upstream of a position where the gas supply amount control means is provided.

According to a third aspect of the present invention, there is provided a burner; a gas supply passage for introducing a fuel gas to the burner; and a gas supply amount provided in the gas supply passage for controlling a fuel gas supply amount to the burner by a valve opening. Control means; and gas flow rate detecting means for detecting a flow rate of the fuel gas supplied to the burner; the burner includes a plurality of combustion surfaces, and each of the combustion surfaces is formed in accordance with the amount of heat of combustion. A burner of a multi-stage capacity switching type is provided, in which relational data between the flow rate of fuel gas supplied to the burner and the combustion heat quantity of the burner is given in advance, and based on the relational data, corresponds to the required combustion heat quantity of the burner. A required gas flow rate detector for determining the required fuel gas flow rate is provided, and the fuel gas flow rate detected by the gas flow rate detecting means is equal to the fuel gas flow rate determined by the required gas flow rate detector. Gas flow rate control unit which controls the valve opening degree performs heat of combustion control of the burner of the gas supply amount control means is a means for solving the problem with a configuration that is provided so as.

According to a fourth aspect of the present invention, there is provided the configuration of the third aspect, wherein a combustion heat amount point at which the lower combustion stage is switched to the upper combustion stage is a combustion heat amount point at which the upper combustion stage is switched to the lower combustion stage. A configuration that is set to a value larger than that is a means for solving the above problem.

According to a fifth aspect of the present invention, the gas supply passage constituting the third or fourth aspect of the present invention is provided with a bypass passage upstream of a position where the gas supply amount control means is provided. The configuration provided with the flow rate detecting means is a means for solving the above problem.

In the invention having the above structure, for example, a gas supply amount control means for detecting a flow rate of the fuel gas supplied to the burner is provided, and a relationship between the flow rate of the fuel gas supplied to the burner and the heat of combustion of the burner is provided. Predetermined data,
The required gas flow rate detecting section detects a fuel gas flow rate corresponding to a required amount of combustion heat of the burner based on the above-mentioned relational data. Is controlled, that is, the amount of gas supplied to the burner is controlled to control the calorific value of the burner.

As described above, since the combustion heat quantity is controlled by controlling the gas flow rate, it is possible to reliably supply the burner with the fuel gas quantity corresponding to the required combustion heat quantity. Further, in a burner having not only one burner but also a plurality of burners, only one data needs to be given to the relationship data between the burner calorie and the fuel gas flow rate. It will be easier.

In the case where the gas flow detecting means is provided in the bypass passage provided in the gas supply passage, the rectifying effect of the bypass passage is reduced by forming the bypass passage smaller in diameter than the gas supply passage. It is higher than the passage, and the rectified fuel gas is supplied to the gas flow rate detecting means, and a detection value without variation is output from the gas flow rate detecting means, so that an accurate fuel gas flow rate can be accurately detected. By performing the combustion heat quantity control using the gas flow rate detection means based on the fuel gas flow rate detected with high accuracy, it is possible to perform the burner combustion more accurately and with the required combustion heat quantity. .

[0026]

Embodiments of the present invention will be described below with reference to the drawings.

The combustion apparatus according to the first embodiment has a system configuration substantially similar to that of the combustion apparatus shown in FIG. 4, and is characterized by being supplied to the burner 1 as shown by a dotted line in FIG. A gas flow sensor 18 serving as gas flow detecting means for detecting the flow rate of fuel gas is provided in the gas supply passage 2, and the combustion calorie control is performed by gas flow control using the fuel gas flow detected by the gas flow sensor 18. That is, a control configuration is provided. In the description of this embodiment, the description of the same components as those of the water heater shown in FIG. 4 will not be repeated.

In this embodiment, as described above, the gas flow rate sensor 18 for detecting the flow rate of the fuel gas supplied to the burner 1 is provided, and the gas flow rate sensor 18 is provided on the upstream side of the proportional valve 6. It is provided in the supply passage 2.

FIG. 6 shows the cross-sectional structure of the proportional valve 6 in a state of being incorporated in the gas supply passage 2. As shown in this drawing, the fuel gas flowing through the gas supply passage 2 flows toward the downstream burner 1 through a narrow opening formed by the valve body of the proportional valve 6. Since the opening area of the opening of the proportional valve 6 is much smaller than the cross-sectional area of the gas supply passage 2, the flow of gas passing through the opening is greatly disturbed.

When the gas flow sensor 18 is provided in the gas supply passage 2 downstream of the proportional valve 6 due to the turbulent gas flow, the detected value output from the gas flow sensor 18 is as shown in FIG. As shown in the figure, there is a problem in that it is very difficult to obtain an accurate gas flow rate from this. However, in this embodiment, as described above, the gas supply passage upstream of the proportional valve 6 is used. Since the gas flow sensor 18 is disposed in the gas flow sensor 2, the gas flow in the rectified state before the gas flow is disturbed by the proportional valve 6 is supplied to the gas flow sensor 18, and the gas flow sensor 18 is caused by the gas turbulence. A detected value without variation is output from the gas flow sensor 18, and an accurate gas flow can be obtained.

The on-off valves 3a, 3b, 3c shown in FIG.
When the gas flow rate sensor 18 is disposed in the gas supply passage 2 on the downstream side, since the gas does not flow to the burner 1 while the combustion is stopped, the gas supply passage 2 There is a possibility that a problem may arise in that air enters the inside of the inside and the gas flow rate sensor 18 detects the flow of the air as a gas flow rate.

On the other hand, by arranging the gas flow sensor 18 in the gas supply passage 2 upstream of the proportional valve 6 as described above, the combustion that enters the gas supply passage 2 from the burner 1 is stopped. Of the air flow of the on-off valves 3a, 3b,
Since the air flow is shut off by 3c, the adverse effect of the air flow does not affect the gas flow sensor 18 and the problem of erroneous detection of the gas flow sensor 18 can be avoided.

FIG. 1 is a block diagram showing a control configuration for performing combustion heat quantity control using a characteristic gas flow rate in the first embodiment. The control device 16 shown in this embodiment includes a combustion calorie detection unit 20, a data storage unit 21, an air flow control unit 22, a required gas flow detection unit 23, and a gas flow control unit 24.

As described above, the combustion calorie detection unit 20 takes the combustion calorie of the burner 1 so that the hot water temperature becomes the hot water supply set temperature Tst set in the remote controller 17 into consideration for the feed-back calorie. Ask for
The calculated amount of combustion heat is output to the required gas flow detection unit 23.

The data storage section 21 stores in advance the relational data between the flow rate of the fuel gas supplied to the burner 1 and the combustion heat quantity of the burner 1 as shown in FIG. It is obtained by experiment or calculation. Since the flow rate of the fuel gas supplied to the burner 1 increases as the amount of combustion heat increases, even in the case of a burner of a multi-stage capacity switching type like the burner 1 shown in this embodiment, the combustion heat amount characteristic data May be only one, and need not be set for each combustion stage.

Since the burner 1 shown in this embodiment is a burner of a multi-stage capacity switching type, a switching combustion calorie point for switching a combustion stage is predetermined in the combustion calorie characteristic data. A point X12 shown in FIG. 2 is a combustion heat amount point at which the first combustion stage is switched to the second combustion stage, and a point X23 is a combustion heat amount point at which the second combustion stage is switched to the third combustion stage. Yes, point X32
Is a combustion heat amount point at which the third combustion stage is switched to the second combustion stage, and point X21 is a combustion heat amount point at which the second combustion stage is switched to the first combustion stage.

Here, the combustion calorie point X12 for switching from the first combustion stage to the second combustion stage is the combustion calorie point X for switching from the second combustion stage to the first combustion stage.
As set to be higher than 21, the combustion calorie point for switching from the lower combustion stage to the upper combustion stage is set higher than the combustion calorie point for switching from the upper combustion stage to the lower combustion stage. .

As described above, each switching combustion calorie point is provided, and the overlap region a,
By providing b, hunting of the switching operation of the combustion stage can be reliably prevented, and the switching of the combustion stage can be performed smoothly.

Upon receiving the information on the amount of combustion heat from the combustion heat amount detection unit 20, the required gas flow rate detection unit 23 compares the amount of combustion heat with the combustion heat amount characteristic data stored in the data storage unit 21 and performs the combustion. The gas flow rate corresponding to the calorific value is detected. For example, when the combustion calorie obtained by the combustion calorie detection unit 20 is the calorie Pex shown in FIG. 2, the gas flow rate corresponding to the combustion calorie Pex in the second combustion stage is the gas flow rate Rex based on the combustion calorie characteristic data. Is detected. In this way, the required gas flow rate detection unit 2
Reference numeral 3 outputs the detected gas flow rate and information on the combustion stage to the gas flow rate control unit 24.

The gas flow control unit 24 controls the opening and closing of the on-off valves 3a, 3b, 3c based on the information of the added combustion stage, and takes in the gas flow rate detected by the gas flow rate sensor 18 every moment. On the basis of the detected gas flow rate of the flow rate sensor 18 and the information of the gas flow rate output from the required gas flow rate detection unit 23, the detected gas flow rate of the gas flow rate sensor 18 becomes the received gas flow rate,
The amount of combustion heat is controlled by controlling the valve opening of the proportional valve 6. That is, when the detected gas flow rate of the gas flow rate sensor 18 is lower than the gas flow rate detected by the required gas flow rate detecting section 23, the valve opening of the proportional valve 6 is controlled in the opening direction for correcting the above-mentioned decrease, and the gas flow rate is controlled. When the detected gas flow rate of the sensor 18 is larger than the gas flow rate detected by the required gas flow rate detecting section 23, the valve opening of the proportional valve 6 is controlled in the closing direction to correct the increase.

There are various control methods for controlling the valve opening of the proportional valve 6 in a direction for correcting the deviation of the gas flow rate detected by the gas flow rate sensor 18 from the gas flow rate detected by the required gas flow rate detecting section 23. In this embodiment, any of these methods may be used, and description thereof will be omitted.

The data storage unit 21 stores air volume control characteristic data as shown in FIG. This data is data of a fan airflow for supplying an appropriate airflow for satisfactorily complete combustion of the fuel gas supplied to the burner 1 to the burner 1 by rotationally driving the combustion fan 8. And the relationship data between the fan airflow and the proportional valve drive current applied to the proportional valve 6 are obtained in advance by experiments, calculations, and the like.

The air flow control unit 22 is provided with the gas flow control unit 24.
, The proportional valve drive current of the proportional valve 6 is detected from the information and referred to the air volume control characteristic data.
Of the fan for completely burning the fuel gas supplied to the fuel cell.

The air flow controller 22 controls the combustion fan 8 so that the supply of the detected air flow is supplied to the burner 1.
To control the rotational drive of. For example, an air volume sensor for detecting the air volume supplied to the burner 1 is provided, and the rotational drive of the combustion fan 8 is controlled so that the air volume detected by the air volume detection sensor becomes the detected fan air volume based on the air volume control characteristic data. I do.

According to this embodiment, the gas flow sensor 18 for detecting the flow rate of the fuel gas supplied to the burner 1 is provided in the gas supply passage 2, and the fuel gas flow rate detected by the gas flow sensor 18 is used. Is provided, the fuel gas amount necessary for burning the burner 1 with the required amount of combustion heat can be reliably supplied to the burner 1, and the burner 1 can be supplied with the required amount of combustion heat. Combustion can be performed. From this, hot water at the hot water supply set temperature can be supplied with high accuracy, and a user of the hot water can be provided with a comfortable use condition of the hot water.

In particular, as in this embodiment, the burner 1
Is a multi-stage capacity switching type burner, the combustion calorie control using the gas flow rate is performed as described above, so that the combustion calorie control using the proportional valve drive current of the proportional valve 6 is performed. It is possible to obtain an epoch-making effect that the calorie control can be easily performed and the burner combustion can be reliably performed with the required amount of combustion heat in a good combustion state.

Since the flow rate of the fuel gas continuously increases as the amount of combustion heat increases, the combustion heat amount control characteristic data for controlling the amount of combustion heat is shown in FIG. 2 regardless of the number of combustion stages. Only one piece of data is required, and it is possible to easily control the amount of combustion heat.

Further, in this embodiment, since the gas flow sensor 18 is provided in the gas supply passage 2 upstream of the position where the proportional valve 6 is provided, the flow rate of the rectified gas is measured by the gas flow sensor 18. Is detected, and a detection value without variation caused by the gas turbulence is output from the gas flow sensor 18, whereby an accurate gas flow can be detected. From this, it is possible to improve the performance of combustion heat quantity control using the gas flow rate.

Hereinafter, a second embodiment will be described. The feature of this embodiment is that a bypass passage 26 is provided in the gas supply passage 2 upstream of the proportional valve 6 and a gas flow sensor 18 is provided in the bypass passage 26, as shown by a chain line in FIG. It was established. The other configuration is the same as that of the first embodiment, and the overlapping description of the common parts will be omitted.

By the way, since the rectifying effect of the fluid flowing through the passage is improved as the diameter of the passage becomes smaller, in this embodiment, the bypass passage 26 is formed to have a smaller diameter than the passage diameter of the gas supply passage 2. The rectification effect is enhanced.

According to this embodiment, the gas supply passage 2
A bypass passage 26 having a higher fluid rectifying effect than
Since the gas flow sensor 18 is provided in the bypass passage 26, a more rectified gas flow can be supplied to the gas flow sensor 18, and a more accurate gas flow can be detected. And based on the accurate gas flow rate thus detected, the first
By performing the combustion heat quantity control in the same manner as in the embodiment, the combustion heat quantity control can be performed more accurately.

The present invention is not limited to the above embodiments, but may take various embodiments. For example, in each of the above embodiments, the burner 1 is a burner of a multi-stage capacity switching type. However, as shown in FIG. 8, the burner 1 is a single-side combustion type burner having one combustion surface. Can also be applied.

Also in this case, for example, a gas flow sensor 18 for detecting the flow rate of the fuel gas supplied to the burner 1 is provided, and the combustion calorie control using the gas flow rate is performed in the same manner as in each of the above embodiments. As a result, similarly to the above-described embodiments, the burner 1 can be reliably burned with the required amount of combustion heat, and the hot water at the hot water supply set temperature can be supplied with high accuracy and supplied to the burner 1. Since air appropriate for the flow rate of the fuel gas is supplied, good combustion can be performed, and deterioration of combustion efficiency can be prevented.
Further, the number of burner combustion surfaces of the combustion equipment to which the present invention can be applied may be two or four or more, and is not limited to the number.

Further, in each of the above embodiments, the combustion heat quantity control characteristic data and the air flow control characteristic data are given by graph data. However, one or both of the above characteristic data can be represented by graph data such as arithmetic expression data. It may be given in a data format other than.

Further, in each of the above-described embodiments, the proportional valve 6 is provided as the gas supply amount control means. However, a gas other than the proportional valve 6 which can control the amount of fuel gas supplied to the burner 1 is used. It may be provided as supply amount control means.

Furthermore, in each of the above embodiments, the description has been made by taking a water heater as an example. However, the present invention can be applied to any combustion equipment that performs burner combustion, such as a bath apparatus other than a water heater, The present invention can also be applied to a hot water / bath complex.

[0057]

According to the present invention, there is provided a structure in which gas flow rate detecting means for detecting a flow rate of fuel gas supplied to a burner is provided, and combustion heat quantity is controlled based on the gas flow rate detected by the gas flow rate detecting means. The fuel gas amount for performing burner combustion with the required amount of combustion heat can be reliably supplied to the burner, so that the burner combustion is performed with the required amount of combustion heat. Hot water at a set temperature desired by the user can be supplied with high accuracy.

In particular, in the case of a combustion device in which the burner is a burner of a multi-stage capacity switching type and performs combustion heat quantity control based on gas flow rate detection means as described above, the flow rate of fuel gas and the combustion rate It is not necessary to provide the relational data of the calorific value for each combustion stage, which makes the control of the calorific value much easier compared to the case of performing the control of the calorific value based on the relational data of the proportional valve drive current and the calorific value. Thus, burner combustion can be performed with a required amount of combustion heat in a favorable combustion state.

In a combustion apparatus in which the burner is a burner of a multi-stage capacity switching type, the combustion calorie point for switching from the lower combustion stage to the upper combustion stage set in the relational data between the fuel gas flow rate and the combustion heat amount However, if the combustion heat point at which the combustion stage is switched from the upper combustion stage to the lower combustion stage is set larger, hunting of the combustion stage switching operation can be prevented, and the combustion stage switching can be performed smoothly. Can be done.

In the case where the gas flow rate detecting means is provided upstream of the interposition position of the gas supply amount control means, the flow rate of the rectified gas upstream of the interposition position of the gas supply amount control means is determined. Is detected by the gas flow rate detecting means, and the gas flow rate detecting means can output a detection value without variation, whereby an accurate gas flow rate can be obtained.

Further, in the case where a bypass passage is provided in the gas supply passage and the gas flow rate detecting means is provided in the bypass passage, the bypass passage is formed to have a smaller diameter than the gas supply passage, so that the bypass passage is formed. Fluid rectification effect is higher than the gas supply passage, and the gas flow rate detection means
A more rectified fuel gas can be supplied, and thereby a more accurate gas flow rate can be detected. As described above, by performing the combustion heat quantity control as described above based on the more accurate detected gas flow rate, more accurate combustion heat quantity control is performed, and the reliability of the combustion heat quantity control can be increased.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a characteristic control configuration in each of the embodiments.

FIG. 2 is a graph showing an example of combustion heat amount control characteristic data used for characteristic combustion heat amount control in each of the above embodiments.

FIG. 3 is a graph showing an example of fan air volume data for supplying an appropriate amount of air to a flow rate of fuel gas supplied to a burner and performing good combustion.

FIG. 4 is an explanatory diagram illustrating an example of a water heater that is a combustion device.

FIG. 5 is a graph showing combustion heat amount control characteristic data and air volume control characteristic data used when performing combustion heat amount control by a proportional valve drive current.

FIG. 6 is an explanatory diagram schematically showing a flow form of a fuel gas in a gas supply passage portion provided with a proportional valve.

FIG. 7 is an explanatory diagram showing a signal waveform output from a gas flow sensor when a flow rate of a turbulent gas is detected.

FIG. 8 is a model diagram showing an example of a burner having only one combustion surface.

[Explanation of symbols]

 Reference Signs List 1 burner 2 gas supply passage 6 proportional valve 18 gas flow sensor 23 required gas flow detection unit 24 gas flow control unit 26 bypass passage

Claims (5)

[Claims] A burner; a gas supply passage for introducing a fuel gas to the burner; a gas supply amount control means provided in the gas supply passage for controlling a fuel gas supply amount to the burner by a valve opening degree; A bypass passage provided in the gas supply passage; gas flow detecting means provided in the bypass passage for detecting a flow rate of fuel gas supplied to the burner; a flow rate of fuel gas supplied to the burner and combustion of the burner The relation data with the calorific value is given in advance and based on the relation data,
A required gas flow rate detector for determining a fuel gas flow rate corresponding to a required calorific value of the burner; a fuel gas flow rate detected by the gas flow rate detecting means is a fuel gas flow rate determined by the required gas flow rate detector. And a gas flow control unit for controlling the valve opening of the gas supply amount control means and controlling the combustion calorie of the burner. 2. The combustion apparatus according to claim 1, wherein the bypass passage is provided upstream of a position where the gas supply amount control means is provided. A burner; a gas supply passage for introducing fuel gas to the burner; gas supply amount control means provided in the gas supply passage for controlling the supply amount of fuel gas to the burner with a valve opening degree; Gas flow rate detecting means for detecting a flow rate of fuel gas supplied to the burner; the burner includes a plurality of combustion surfaces, and a plurality of stages capable of switching each of the combustion surfaces according to the amount of combustion heat. A switchable burner is provided, in which relational data between the flow rate of fuel gas supplied to the burner and the calorific value of the burner is given in advance, and based on the relational data, the fuel gas flow rate corresponding to the required calorific value of the burner A required gas flow rate detection unit for obtaining the required gas flow rate, and the fuel gas flow rate detected by the gas flow rate detection means is equal to the fuel gas flow rate determined by the required gas flow rate detection unit. A combustion apparatus comprising a gas flow control unit for controlling a valve opening degree of a gas supply amount control means and controlling a combustion heat amount of a burner. 4. A combustion heat amount point at which a lower combustion stage is switched to an upper combustion stage is set to a value larger than a combustion heat amount point at which an upper combustion stage is switched to a lower combustion stage. The combustion device according to claim 3, characterized in that: 5. A gas supply passage, wherein a bypass passage is provided upstream of a position where the gas supply amount control means is provided, and a gas flow rate detection means is provided in the bypass passage. The combustion device according to claim 3 or 4, wherein